Magnetic and relaxometric properties of Mn ferrites

We present the magnetic properties and the 1H nuclear magnetic resonance dispersion profiles of Mn-ferrites-based compounds, as possible novel contrast agents (CAs) for magnetic resonance imaging (MRI). The samples consist of nanoparticles (NPs) with the magnetic core made of Mn1+xFe2-xO4, obtained...

Full description

Saved in:
Bibliographic Details
Published in:Journal of physics. D, Applied physics Applied physics, 2008-07, Vol.41 (13), p.134021-134021 (6)
Main Authors: Boni, A, Marinone, M, Innocenti, C, Sangregorio, C, Corti, M, Lascialfari, A, Mariani, M, Orsini, F, Poletti, G, Casula, M F
Format: Article
Language:English
Subjects:
Condensed matter: electronic structure, electrical, magnetic, and optical properties
Diamagnetism, paramagnetism and superparamagnetism
Exact sciences and technology
Magnetic properties and materials
Magnetic resonances and relaxations in condensed matter, mössbauer effect
Nuclear magnetic resonance and relaxation
Physics
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We present the magnetic properties and the 1H nuclear magnetic resonance dispersion profiles of Mn-ferrites-based compounds, as possible novel contrast agents (CAs) for magnetic resonance imaging (MRI). The samples consist of nanoparticles (NPs) with the magnetic core made of Mn1+xFe2-xO4, obtained by the rapid decomposition of metalcarbonyl into a hot solvent containing an oxidizer and a coordinating surfactant; by this procedure, monodisperse capped NPs with different sizes have been obtained. We have performed structural and morphological investigation by x-ray powder diffraction and transmission electron microscopy techniques and SQUID magnetometry experiments to investigate the magnetic behaviour of the samples. As required for MRI applications using negative CAs, the samples are superparamagnetic at room temperature, having blocking temperatures in the range 14-80 K. The longitudinal r1 and transverse r2 nuclear relaxivities appear to vary strongly with the magnetic core size, their values being comparable to commercial compounds in the high-frequency range nu > 100 MHz. The experimental results suggest that our samples are suitable for high-frequency MRI imagers in general and in particular for the 3 T clinical imager, as indeed suggested by a recent report (Tromsdorf et al 2007 Nanoletters 7 2422).
ISSN:0022-3727
1361-6463
DOI:10.1088/0022-3727/41/13/134021